A study on the Porosity Characterization of U$_3$Si$_2$ Dispersion Fuel prepared with Atomized and Comminuted Powders

To investigate the effects of powder shape on U loading density of fuel meat, two kinds of fuel meats were prepared with atomized and comminuted U$_3$Si$_2$ powders by extrusion or rolling process. Extruded fuel meats with atomized spherical U$_3$Si$_2$ powder appeared to have much less porosity than those with comminuted irregular U$_3$Si$_2$ powder at higher U$_3$Si$_2$ fraction- The U$_3$Si$_2$ particles with spherical shape are less fractured in extrusion than in rolling. Most of atomized particles on the whole maintained to have spherical shapes in the extrusion. It has been shown that atomized spherical particles are expected to approach similar upper loading limits comparing with comminuted particles in rolled plates, but exceed comminuted powder loading limits in extruded rods.